IEEE 802.16m擁有高傳輸速度與高頻寬的優點，因此在未來它將在無線通訊系統中扮演著重要的角色，在IEEE 802.16m裡我們時常在二維Resource Block中的某些位置上插入pilot，並且去估測出這些pilot的通道頻率響應，使用這些估測出的通道頻率響應來估測出Resource Block中的其他位置的通道頻率響應，本論文在插入這些pilot時考慮了三個議題，在Resource Block中使用最小的pilot數量以便於放置最多的傳輸資料，但它仍需要有足夠的pilot數量來準確地估測出通道的頻率響應，同時，這些pilot必須能夠在適當的場所減少行動台的使用者與基地台間之干擾，本論文中提出設計的程序在於如何去估計pilot與pilot之間的干擾，如何計算pilot在Resource Block中的佔有率，如何放置pilot的位置可以產生最低的干擾；在通道頻率響應的估測中我們使用了最小平方差以及最小均方差兩種方法，基於我們所提出的pilot設計方式，我們提出了一幾個2x2 MIMO系統中pilot放置的例子，並且對模擬這些例子對於系統的干擾程度並且使用MMSE估測出通道頻率響應，使用這些模擬的結果來證實我們的設計理念與模擬的演算法是否正確。

For IEEE 802.16m system it possesses the advantages of high transmission speed and broad bandwidth it will play an important role in the future wireless communication services. In IEEE 802.16m system it usually inserts pilot tones in certain locations of the two dimensional Resource Block to estimate the channel impulse responses at those locations and then uses certain interpolation techniques to find the channel responses at other locations. Three issues need be considered in the insertion of these pilots. It needs to use a minimum number of pilot tones so as to reserve maximum number of resources for data transmission, but it needs to have enough pilot numbers so as to generate accurate estimate of the channel impulse responses and meanwhile it needs to insert these pilots at proper locations to minimize the possible interferences from outer base stations and mobile users. In this thesis we propose the design procedures of how to measure the interference between pilots, how to calculate the pilot occupancy percentage, and how to insert pilot locations to generate possible minimum interferences. In the channel impulse response estimation both the least square (LS) and the Minimum Mean Square Error (MMSE) are considered. Based on our pilot design principle we propose the number and locations of pilots in 2 x 2 systems, and to simulate the resulting system interference levels and to find the resulting MMSE in the channel impulse response estimation. It will use the simulation results to validate our design principle and simulation algorithm.

目錄
第一章	緒論 ...…………………….….………..1
1.1研究動機與目的 …….…………………….……...1
1.2章節介紹 ……...………..………..………………..2
第二章	無線通訊系統之通道估測 ..................3
2.1系統流程架構 ………………………….……........3
2.2通道模型 …………………………………………..4
2.2.1多路徑通道 ……………………………………………....4
2.2.2都卜勒位移 ………………………………………………5
2.3 通道估測 …...…………………………………….6
2.3.1二維通道估計法 …………………………………………6
2.3.2最小平方法 ………………………………………………7
2.3.3最小均方差法	……………………………………………8
第三章	IEEE 802.16m無線通訊系統Pilot之設計理念……………………………………….11
3.1 Frame structure for IEEE 802.16m ....…………11
3.2 STBC 應用於2x2 MIMO Pilot structure ……..12
3.3高速度移動之pilot設計 ………………………...15
第四章	Pilot設計之模擬研究…..………........17
4.1模擬環境..……….………………………………...17
4.2各種不同型態RB架構的模擬…………………..19
4.2.1 Type A之RB架構 ……………………………………..19
4.2.2 Type B之RB架構 ……………………………………..25
4.2.3 Type C之RB架構 ……………………………….........31
4.2.4 Type D之RB架構 ………………………………….....36
4.2.5 Type E之RB架構 …………………………………….41
4.2.6 Type F之RB架構 ……………………………………...47
4.2.7 Pilot設計彙整…………………………………………...51
4.2.8 Pilot Coefficient ………………………………………...52
第五章	結論與未來展望 ……………………55
                     
參考文獻 ………………...………………57
圖目錄
圖2.1  系統傳輸流程架構 ……….………………………………………...4
圖2.2  Pilot位置圖 ………………………………………………………...7
圖3.1　IEEE 802.16m的Frame Structure ………………………..………12
圖3.2  STBC傳送與接收訊號示意圖 …………………………………...13
圖3.3  STBC編碼示意圖 ………………………………………………...14
圖3.4　STBC編碼後之Resource block …………………………………...15
圖3.5　高移動速度之Resource Block示意圖 …………………………...16
圖4.1  Type A-Type F之原始RB ……........................................................19
圖4.2  Type A的各種型態分類示意圖  ………………………………...20
圖4.3  Type A時速(a)3 km/hr、(b)60 km/hr、(c)120 km/hr下之模擬結果示意圖 ……………………………………………………………………...23
圖4.4  Type B的各種型態分類示意圖 ………………………………….26
圖4.5  Type B時速(a)3 km/hr、(b)60 km/hr、(c)120 km/hr下之模擬結果示意圖 ……………………………………………………………………...29
圖4.6  Type C的各種型態分類示意圖…………………………………...32
圖4.7  Type C時速(a)3 km/hr、(b)60 km/hr、(c)120 km/hr下之模擬結果示意圖 ……………………………………………………………………...35
圖4.8  Type D的各種型態分類示意圖…………………………...………37
圖4.9  Type D時速(a)3 km/hr、(b)60 km/hr、(c)120 km/hr下之模擬結果示意圖 …………………………………………………………………...…40
圖4.10  Type E的各種型態分類示意圖 …………………………………42
圖4.11  Type E時速(a)3 km/hr、(b)60 km/hr、(c)120 km/hr下之模擬結果示意圖 ……………………………………………………………………...45
圖4.12  Type F的各種型態分類示意圖 …………………………………47
圖4.13  Type F時速(a)3 km/hr、(b)60 km/hr、(c)120 km/hr下之模擬結果示意圖 ……………………………………………………………………...50
圖4.14  Pilot簡易設計概念 …………………………..………………….52
圖4.15  Pilot Coefficient示意圖…………………………………………...54
圖4.16 矩形型態Pilot Coefficient組合示意圖……………………………54
圖5.1 Type F在350 km/hr的MMSE模擬示意圖………………………….56
圖5.2 Type F在500 km/hr的MMSE模擬示意圖……………………..…56
 
表目錄
表3.1  傳送端的編碼方式 …………………………………………...12
表4.1  模擬參數 …………………………………………………….. 18
表4.2  1024 FFT OFMDA UL Subcarrier Allocation ...........................18
表4.3  Type A在BER為 時的SNR值 …………………………24
表4.4  Type B在BER為 時的SNR值 …………………………30
表4.5  Type C在BER為 時的SNR值 …………………………35
表4.6  Type D在BER為 時的SNR值 …………………………40
表4.7  Type E在BER為 時的SNR值 …………………………...46
表4.8  Type F在BER為 時的SNR值 …………………………...50

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